Loud Grinding Noise
 

Have had an issue arise where I get a rather loud grinding noise that seems to come from the transmission, unsure whether the gearbox has gone or whether its the clutch. As far as I'm aware the car has not been well looked after since I got it, figured it was time that something big went wrong.

It grinds in all gears (also neutral), only stops when you put the clutch pedal down, grinding gets louder when you accelerate, then quietens down when you let off. Just want to know peoples thoughts before I have a crack at anything. Thanks people